Asphalt, bitumen, or rubberoid shingles are currently decorated with pre-colored aggregate and/or granules to provide texture and color. The pre-colored aggregate/granules are applied via an analog waterfall technique after asphalt coating, followed by press rolling and finishing. Multiple analog application processes and spot color storage facilities are required to produce a specific design.
FIG. 1 represents the current method of applying decorative granules to roofing substrates, in which a fiberglass mat 10 is spliced at a splice table 12. The spliced mat is passed to a mat accumulator 14, and then coated with asphalt at an asphalt coater 16. Aggregate/granules are applied to the asphalt coated surface of the fiberglass mat 18. A release tape assembly 20 and cooling assembly 22 further process the now coated mat. Finally, the mat is cut into shingles 24, bundle wrapped 26, and palletized 28. This is shown to highlight some of the limitations of the current method (see, also, http://www.carmeusena.com/sites/default/files/shingelmfg.jpg).
Currently, color is applied more or less at random after the asphalt is applied to the fiberglass mat using pre-colored granules to achieve the desired hue, shade, tint, and tone. The current application method of granules precludes the use of current manufacturing techniques to generate more complex patterns, e.g. wood grain or stone, on the surface of the roofing material.
Patent application no. US2007/0077361, entitled Roofing Articles with Reflective Thin Films and the Process of Producing the Same, relates to the process of improving the infrared reflectance of roofing materials through the vacuum deposition application of silver, aluminum, copper, zinc, tin, gold, palladium, nickel, and alloys thereof. One section of the patent speaks to the possibility of applying a transparent coating of metal and nonmetal oxides to improve the long-term durability of the underlying coating.
PCT patent application no. WO/2005/094444, entitled A Building Membrane, describes thermoset plastics that are used to generate a single-layer coating for different types of building materials, including asphalt or bitumen shingles, as well as tile, slate, wood, and brick materials. The coating may be applied using a variety of techniques, such as flexo, gravure, and inkjet.
Patent application No. US20060229382, entitled Water Based Coloring Agent Preparations for Inkjet Printing, describes a water based-formulation for organic pigments to be inkjetted onto various substrates including roofing shingles. A curable, organic binder system is used to provide adhesion to the substrate and continuity of the film.
U.S. Pat. No. 8,932,718, entitled Coating Systems for Cement Composite Articles, describes a system comprised of latex or epoxy resins, possibly in an aqueous continuous phase, used to coat various architectural materials, specifically cements, cement fiberboard, wood, and glass fiber substrates.
PCT patent application no. WO 2014111608, entitled Coloured Frits with a Lustre Effect, relates to the application of colored, metallic frits that can be applied to ceramic, glass, or metal substrates to provide decoration of the aforementioned substrates. These frits must be fired to achieve the desired effect. The potential for printing on roofing shingles is mentioned in one paragraph. However, no clear method or formulation is outlined specifically for this application.